The assignment: You are on a team working with the City of Chicago on increasing the City’s tree canopy from just under 15% to 25%. What would you recommend? Please bear in mind that most city staff feel that they have covered most city owned land and that to reach the goal they will have to get private landowners to plant the trees. How can we get them to do this? What types of parcels present opportunities?

The class: Sustainable Development Techniques

How the class works: The professors invite working professionals to speak to the class each week. After the lecture from these guests, a short discussion ensues. The guests design the homework questions. The following week, the class discusses their responses with each other and the professors.

I’ve identified four parcel types that present opportunities to increase the City of Chicago’s tree canopy from 15% to 25%.

1. Existing surface parking lots, both private and public
2. New surface and multi-level parking lots, both private and public
3. Schools, both public and private
4. Condemn private lots

1. The team will inventory private and public surface parking lots. Using demand survey data, the team will identify specific lots and direct them to reduce the number of spaces by half the difference between demand and availability. The team will select the spaces where trees will be planted at no cost to the parking lot owner. Alternatively, the parking lot owners can choose to purchase and install secure, sheltered bicycle parking on the spaces where trees would have been planted. Owners must install this facility at their own expense but may charge for its use.

The owners choose between a no cost option that potentially reduces their income, or a cost option that potentially reduces their income. Both options would potentially reduce carbon or carbon emissions associated with the parking lot.
2. The team will recommend zoning code changes that reduce the number of required auto parking spaces for new parking lots, increase the number of bicycle parking spaces, and improve the zoning code’s accommodations to alternative fuel, hybrid and shared car spaces. The code will require that builders plant trees in the space that would have been built as auto parking. The code will specify best tree planting practices so the builders plant trees in places on the parcel where it will live.

Parking lots will become useful to a larger number of users, and reduce carbon in the atmosphere.

3. Many schools have land paved with asphalt, acting either as a playground or parking lot for staff. Under a district (or diocese) and City-wide plan to reduce carbon emissions and improve the health of staff, schools will install sheltered bicycle parking on a small portion of the asphalt, and then remove a large area of asphalt. They’ll replace the removed asphalt with grass and trees. Principals will make up the first group of staff to adopt alternative commute methods (which can include carpool, vanpool, transit, walking or bicycling), starting with at least two days per week.

Students will receive a kid-friendlier playground. School staff will reduce their carbon emissions. Schools will help reduce their contribution to the urban heat island effect. New trees will reduce carbon in the atmosphere.

4. Lastly, the City will condemn private lots and convert these to urban forests. The team will first identify residential areas, and then commercial areas. Communities identified by the team to receive urban forests can choose to have and operate a farm or garden instead. The City will provide relocation assistance to all residents of a blighted or energy inefficient building who decide to move to a denser part of the city. The City would then condemn the lot and building, aggregating it into the forest. A variation of this plan includes strategic placement of the trees: The trees can be planted in such a way on the parcel’s perimeter that would permit a new parcel owner to build a new, energy efficient home on the lot.

I feel unclear about the consequences of this strategy. Will the new urban forests raise, lower, or leave alone property values? Will property owners appreciate a rise in property values? Will they feel their neighborhood has improved? How will the forests affect crime and other neighborhood activities?